   :scp-options       a scp options string
   :rsync-options    a rsync options string.
   :user                    global user for cluster,if cluster do not have :user ,it will use this by default.
+  :parallel               if to execute task on remote machines in parallel,default is false
 
   Example:
         (set-options! :ssh-options \"-o ConnectTimeout=3000\")

      (alength p)
      3)))

(defn do-begin [args]
  (when-exit (< (count args) 2)
             "Please offer cluster and task name"

  "
  [key value & kvs]
  (let [options (apply hash-map key value kvs)]
    (check-valid-options options :user :ssh-options :scp-options :rsync-options :parallel)
    (swap! *global-options* merge options)))
  
(defn clear-options!
